Looper-supporting mechanism for sewing-machines



I. R. MOFFATT. LOOPER SUPPORTING MECHANISM FOR SEWING MACHINES.

l w L 3 5 7 1 APPLICATION FILED JULY IT- I9I7- Patented Apr. 19, 1921. 2 SHEETSSHEET I- 314w ntoz J. R. MOFFATT. LOOPER SUPPORTING MECHANISM FOR SEWING MACHINES.

APPLICATION FILED JULY I7. 1917- 2 SHEETSSHEET 2.

Patented Apr. 19, 1921.

mm a M UNHT JAMES MOFFATT, O33 CHICAGO, ILLINOIS, ASSIGNOB T0 UNION SPECIAL MACHINE COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS. V

LOOZPER-SUPPORTING MECHANISIE FOR SEWING-MACHINES.

Specification of Letters Patent.

Patented Apr. 19, 1921.

Application filed July 17, 1917. Serial No. 181,092.

T 0 aZZ whom it may concern:

Be it known that I JAMEs R. MorFATr, a citizen of the United tates, residing at Chicago, in thecounty of Cook, State of 1111- nois, have invented certain new and useful Improvements in Looper-Supporting Meclr anism for Sewing-Machines, of which the following isa description, reference being had to the accompanying drawing and to the figures of reference marked thereon.

The invention relates to new .and useful improvements in looper-supporting mechanisms for sewing machines, and more particularly to a looper support on which two loopers are mounted which are adapted to cooperate respectively with needles.

An object of the invention is to provide means whereby the loopers may be adjusted toward and from the needles and relative to each other, without disturbing their angular position relative to a horizontal line, whereby said loopers will maintain uniform drags on their respective needle thread loops during the loop-shedding movement of said loopers, and also permit the simultaneous shedding of said loops.

In the drawings,

Figure 1 is a front view of a sewing machine having my improvement applied thereto, the work support being broken away to show the looper-carrier and the looper support therefor;

Fig. 2 is an enlarged front view of the looper-carrier;

Fig. 3 is a rear view of the same;

Fig. 4C is a perspective view of the looper from the rear, showing the parts separated;

Fig. 5 is a diagrammatic view, showing the manner of adjusting the loopers; and

Fig. 6 is a view similar to Fig. 3,. but showing a slightly modified form of the invention.

The invention is directed particularly to a two-needle machine having a looper cooperating with each needle and wherein the loopers are mounted so as to move in planes at right angles to the line of feed. The two loopers are mounted on the same looper-carrier and this looper-carrier is oscillated and moved sidewise for giving the loopers their proper movements.

It has been customary to form the link for oscillating the looper-carrier, so that the carrier may be shifted for, properly setting the loopers relative to the needles. The loopers should simultaneously cross their respective needles when entering the needle thread loops just above the eyes in the needles and by adjusting the link this timing of at least one looper may be accomplished. It sometimes occurs that when one looper is properly adjusted to cooperate with its needle, the other looper is out of timing, and the present invention is directed particularly to a means for mounting one of the loopers on the looper-carrier, so that it may be adj usted bodily for bringing out a proper timing or setting thereof relative to its needle after the other loop has been properly set by adjusting said link.

Furthermore, it is essential that both needle loops shall be dropped or released simultaneously by the loopers, so that a single thread-controlling means may be used for both needle threads. The adjustment of the loopers above referred to will accomplish this result, provided the drag of the loopers on their respective needle thread loops has not been changed. The ad usting means is,

therefore, so constructed that the looper may be shifted bodily without disturbing or changing its drag on its needle loop.

Referring more in detail to the drawings, I have shown my improved looper supporting mechanism as applied to a sewing ma chine having a bed plate 1, an overhanging arm 2, in which a needle bar 3 reciprocates.

This needle bar carries two needles 4 and 5. These needles 4 and 5 are set in a line diagonal to the line of feed. Cooperating with the needle lis a looper;- and cooperating with the needle 5 is a looper 6.

These loopers are mounted on a looper carrier 8 which is pivoted at 9 to a looper support or rocker 10. The looper carrier is oscillated by means of a link 11 which is connected to the ball stud 12 on the looper carrier.

The other end of this link is con- 4 nected at 13 to the needle lever extension 14' the link will either shorten the link or lengthen the same. Adjustably mounted on the main looper carrier 8' is an auxiliary looper carrier 19.- The main looper carrier is formed with a rib 20 while the auxiliary 25 formed therein.

carrier is formed with a groove 21. Said.

auxiliary carrier has an elongated slot 22 Y relative thereto. The rib and groove are arranged in a line at right angles to the longitudinal center of the main part of the carrier. i

The main looper carrier 8 has a socket for the looper 7 and saidlooper is heldin the socket by means of a set screw 24. The auxiliary looper carrier has a transverse socket A sleeve 26 has a later ally extending stud 27 which is adapted to be received by said socket 25 and a set screw 28 serves to lock the stud in place. Said stud has a flat side which serves to hold the sleeve in a position with its longitudinal axis substantially parallel with the longitudinal axis or center of the main looper carrier.

The looper 6 has a. shank which is mounted in this sleeve and a setscrew 29 serves to i hold the shank in place in the sleeve. By

diagrammatically the needles 4 and 5 and the looper-s 6 and 7. Let us assume that p the link 11 has been adjusted so as to shift the carrier to properly position the looper 7 so that the point of this looper will cross the needle just above the eye of the needle as it enters the needle loop. Let usassume also that owing to a faulty construction of the looper, when the looper 6 is properlytimed as above noted, that the looper 7 .is slightly out of timing. That is, its point is back from the needle .4, as shown in this figure of the drawings The pivotal center of the looper carrier, that lStllG axis about which the looper carrier turns, is indicated at 9 in said figure. The outer curved surface of the looper is concentric with this pivot point of the carrier and is indicated by the full circular line a-a. The under surface of the looper, as is well fknowrnis curved about a point shghtly to the right of the center 9*, so that its curved surface is eccentric to the needle on its next descent. The angular position of this eccentric surface to a hori zontalline also determines the time of dropping or shedding of the needle loop.

In the drawings I have indicated the chord of the outer" curved surface f the looper 6 by the line b. By loosen ng the screw which holds the auxiliary carrier, said auxiliary carrier may be shifted bodily in a line parallel with the line 00 -02, which is at right angles to the longitudinal line or axis y n of the main looper-carrier. This shifts the chord b to the position indicated by the broken line a. While the looper point has been brought up to the needle it is slightly above the position where it should be when it crosses the needle to enter the. needle loop, and, therefore, thelooper is then bodily adjusted vertically to. bring the chord of its outer curved surface to'the line 01. It will be noted that the chords 0, 'Z) and d are all parallel, and, therefore, the looper6 has been adjusted and properly'set without disturbing the position of the eccentric surface.

By thus maintaining the curved surface of the looper 6 always in the same posit-ion relative to the looper 7, I am able to adjust the looper, and when-the'loopers'are in their several adjusted positions, they will simultaneously drop the needle loops. It will be readily understood that if the looper 6 be shifted about the pivot point for adjust ment, then the under'curved surface will be varied or shifted from its original position and will either hang onto the needle loop 7 longer or release it a little. quicker. It is essential that both the needle loops should be dropped simultaneously, as in this type of machine it is desirableto use a single thread controlling mechanism for both threads. The adjustments described enable the loopers to be brought into proper timing and both loopers will also shed their needle loopsat exactly the same time.

The auxiliary carrier 1s shown as provided with a large opening for the screw 29. This permits the aux1l1ary carrier to be a adjusted andat'the' sametime the set'screw is readily accessible.

' In the modification shown in Fig. 6, the loopers' 6 and 7 are carried by the main looper carrier 8 andthe looper 6 is mounted in anauxiliary carrier 19 which is adjustably mounted on the main looper carrier and held in adjusted position by means of a screw 19; A looper 6 is formed with a vertically disposed shank adapted to enter a socket formed directly in the auxiliary carrierand said looper is held in said socket by meansof a screw 19 1' The auxiliary carrier is provided with a laterally extending lug 30 and a stop screw 31 extends up through this lug. The purpose. of the stopv screw is to fix the vertical position of the looper 6 so that it may be readily removed and replaced and when replaced it can be broughthack to the same set position against the stop. The auxiliary carrier is held from movement about the screw 19 by a ledge 32 onwhich itrests.

From the above description it will be apparent that the looper 6 may be adjusted in a direction substantially at right angles to the longitudinal axis ofthe looper carrier by shifting of the auxiliary carrier on the main carrier and that the looper may be adjusted bodily vertically by releasing the screw 19 and shifting'the stop screw 31. Through these two adjustments the looper may be timed in the manner above described.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is I 1. The combination with a pair of needles, of a looper coiiperating with each needie, a looper-carrier for both loopers, and means whereby one of said loopers may be adjusted relative to the other of the loopercarrier and in a direction substantially at right angles to the longitudinal axis of the looper-carrier without disturbing its position relative to a horizontal line at the time of shedding its needle-thread loops.

2. The combination with a pair of needles, of a looper for each needle, a loopercarrier on which said loopers are mounted, one of said loopers being mounted directly on said carrier, and an auxiliary carrier for the second looper, means for adjustably 'se-' curing said auxiliary carrier to the main looper-carrier, whereby said auxiliary carrier may be shifted bodily in a direction substantially at right angle to the longitudinal axis or" the looper-carrier and without disturbing its position relative to a horizontal line.

3. The combination with a pair of needles, of a looper for each needle, a loopercarrier on which said loopers are mounted, one oi said loopers being mounted directly on said carrier, and an auxiliary carrier for the second looper, means for adjustably securing said auxiliary carrier solely to the main looper-carrier, whereby said auxiliary carrier may be shifted bodily in a direction substantially at right angles to the longitudinal axis oi the looper-carrier and without disturbing its position relative to a horizontal line, and means whereby said second looper may be adjusted toward and from the center of the looper-carrier.

l. The combination with a pair of needles, of a pivoted looper carrier, means for swinging said looper carrier about its pivot, including devices whereby the oscillating position of the looper carrier may be shifted, a looper for each needle mounted on said carrier, one of said loopers being mounted directly on .the carrier and an auxiliary looper carrier for the other looper, means whereby said auxiliary looper carrier may be shifted bodily in a direction substantially at right angles to the longitudinal axis of the carrier and without disturbing its position relative to a horizontal line, and means whereby the looper may be adjusted toward and from the center of the looper 'carrier on said auxiliary carrier.

5. The combination with a looper'carrier having a socket for a looper, means for holding the looper in the socket, an auxiliary carrier adjustable vertically at right angles to the longitudinal axis of the main carrier, said auxiliary looper carrier and main carrier having a rib and groove connection disposed so as to permit the auxiliary carrier to be adjusted in a direction substantially at right angles to the longitudinal axis of the main carrier, a second looper mounted on said auxiliary carrier.

'7. The combination with a looper carrier adapted to be bodily supported, said looper carrier having a socket for the looper, a looper mounted therein and means for bolding the looper in said socket, an auxiliary looper carrier mounted in the main looper carriensaid auxiliary looper carrier and main carrier having a rib and groove connection disposed so as to permit the auxiliary carrier to be adjusted in a direction substantially at right angles to the longitudinal axis of the main carrier, a second looper mounted on said auxiliary carrier, said auxiliary carrier having a transverse socket, a sleeve having a projecting stud mounted in said socket, means for holding the stud insaid socket whereby it may be adjusted in a direction at right angles tov the plane of movement of the looper carrier, said sleeve having a socket for said second looper and means for adjustably supporting said looper in said socket.

8. The combination with a looper carried adapted to be bodily supported, said looper carrier having a socket for the looper, a looper mounted therein and means for bold 'ing the looper insaid socket, an auxiliary looper carrier in the main looper carrier,

said auxiliary looper carrier and main carrier having a rib and groove connection disposed so as to permit the auxiliary carrier to be adjusted in a direction substantially at right angles to the longitudinal axis of the main carrier, a second looper mounted on said auxiliary carrier, said auxiliary carrier having atransverse socket, in said socket and an adjustable stop for a sleeve having a projecting stud mounted positioning the looper in the sleeve. 7 10 in said socket, means for holding the stud In testimony whereof I afiix my signature in said socket whereby it may be adjusted in the presence of two witnesses.

in a direction at right angles to the plane of JAMES R. MOFFATT. movement of the looper carrier, said sleeve Witnesses:

having a socket for said second looper and J. H; MAsLAND,;

means for adjustably supporting said looper STEDMAN THOMAS. 

